This week’s UK average pump prices
The formula
Litres = miles ÷ mpg × litres per gallon. Cost = litres × pence per litre ÷ one hundred.
UK mpg uses the imperial gallon: an imperial gallon is 4.54609 litres2. A US gallon is smaller (a US gallon is 3.785 411 784 litres3), which is why the same vehicle shows a higher mpg in UK figures than in US ones.
Official figures for one common hire campervan
| Vehicle | WLTP combined |
|---|---|
| VW California Ocean, diesel | 40.7 mpg (WLTP combined, worst case), VW California Ocean 150PS 2.0 TDI diesel4 |
| VW California Ocean, petrol | 30.2 mpg (WLTP combined, worst case), VW California Ocean 204PS 2.0 TSI petrol4 |
VW says WLTP figures are for comparison and may not reflect real driving4. Coachbuilt motorhomes are heavier and taller; their makers usually publish no mpg for the finished vehicle, so the calculator leaves mpg empty for them. Ask the hire company, or use the figure from your own fill-ups.
Work out your own trip: open the motorhome hire calculator. It starts with sourced defaults and leaves the rest for your quote.
Sources
- Department for Energy Security and Net Zero (DESNZ), Weekly road fuel prices, data for the week of 26 October 2026. Checked 31 October 2026. Open Government Licence v3.0. GOV.UK Content API → CSV attachment (no key needed).
- Weights and Measures Act 1985, Schedule 1 (legislation.gov.uk). Checked 31 October 2026.
- NIST Handbook 44 (2026), Appendix C. Checked 31 October 2026.
- Volkswagen Commercial Vehicles UK, California brochure (2026). Checked 31 October 2026. Brochure PDF dated March 2026; its footnote says the data were correct at 26.6.2023.